In musical entertainment, there are styles of music that rely on the amplification of a harmonica by utilizing a microphone and an amplifier. In cases where the harmonica needs to be amplified to a level where a large audience can hear, audible feedback typically occurs due to the interaction of the microphone properties with the high amplification level. This audible feedback forces the artist to maintain a lower volume level and therefore a lower projection of sound.
There have been attempts to reduce feedback in the past through the use of resistor and capacitor networks, however, these attempts altered the normal sound of the amplifier which in most cases is not a positive consequence.